Olmesartan medoxomil, known from EP 503785, incorporated into a pharmaceutical composition may be used as an angiotenzin II antagonist. Chemically it is a 4-(1-hydroxy-1-methylethyl)-2 propyl-1-[[2′-(1H-tetrazol-5-yl) [1,1′-biphenyl]-4-yl]methyl]-1H-imidazole-5-carboxylic acid (5-methyl-2-oxo-1,3-dioxol-4-yl)methyl ester. Although olmesartan medoxomil is a prodrug that is hydrolyzed during absorption and it is marketed as Benicar or Olmetec in tablets for treatment of hypertension, it is not desirable that it hydrolyzes prior to ingestion.